Two-sided pickup and stylus therefor



March 17, 1953 s. B. BAUER TWO-SIDED PICKUP AND STYLUS THEREFOR 2SHEETS-SHEET 1 Filed Oct. 1, 1947 VII/IlII/YII/III/II/II/MII R m M W.

March 17, 1953 B. B. BAUER 2,531,857

TWO-SIDED PICKUP AND STYLUS THEREFOR Filed on. 1, 1947 2 SHEETS SHEET 2IN V EN TOR.

j flil wwn Patented Mar. 17, 1953 UNITED STATES OFFICE TWO-SIDED PICKUPAND STYLUS THEREFOR Benjamin B. Bauer, Oak Park, 111,, assignoi' toShure Brother's, Incorporated, Chicago, 111., a "corporation of IllinoisApplication October -1, 1947; Serial-No. 777,284

6 Claims.

This invention relates to sound translating units or pickup units forphonographs, more particularly to such units for playing the top of onephonograph record and the bottom of another phonograph record withoutturning the record over.

Phonogra-phs frequently include record changing apparatus for playing aplurality of records, and the phonograph will play one side of each ofthe records until the series of record is completed. Thereupon it isnecessary to turn the records over so that the'other sides thereof maybe played. This results in time delays and broken records due, forexample, to inadvertent dropping thereof during the necessary handling.

It has been suggested that phonograph appara: tus be constructed whereineach record is turned over automatically whereupon all sides may beplayed with well known pickup and tone arm constructions. Such apparatusis bulky, complicated and difiicult to service. Accordingly, it is afurther object of the invention to provide im-'- proved phonograph tonearm apparatus for playing both sides of a record without turning therecord over.

It is-a further object of the invention to provide an improvedphonograph pickup for playing both sides of a record.

it is a further object of the invention to provide an improved two-sidedphonograph pickup.

It is a further object of the invention to provide, in combination, atwo-sided pickup and an improved double-ended stylus.

It is a further object of the invention to provide an improveddouble-ended stylus.

It is a further object of the invention to provide improved means forpositioning a doubleended stylus in a phonograph pickup.

It is a further object of the invention to provide a stylus withimproved means for orientation thereof.

In carrying out the invention in one form, a translating unit forreproducing the upper and lower sides of a record in a phonographwithout turning the record over has been provided comprising a casing tobe removably held in the tone arm of a phonograph, a translating elementin the casing,a drive member operable to actuate the translatingelement, said drive member including a stylus receiving opening, saidcasing including an opening on each side thereof in stylus alignmentwith said receiving opening, and a doubleended stylus having a holdingportion in said receiving opening and having a pair of record engagingportions projecting outwardly through said aligned openings, said stylusincluding meansassocia-ted with said holding portion "for indicatingapproximate location of the stylus in the pickup unit, said holdingportion including means cooperating with said pickup for'e'xact locationof the stylus therein. I

For a more complete understanding of the invention reference should behad to the accompanying drawings in which:

Fig. 1 is a fragmentary view in perspective of apparatus embodying theinvention;

Fig. 2 is a fragmentary elevational view partially in section ofapparatus shown in Fig. l;

Fig. 3 is a fragmentary sectional view on a larger scale of theapparatus shown in Fig. 1;

Fig. 4 is a fragmentary viewon a larger scale of the apparatus shown inFig. 3; and y Fig. 5 is a view similar to Fig. 3 or a 'm'odified form ofthe invention.

Referring to the drawings, the invention is shown as comprisingphonograph reproducing apparatus including a pair of records 10 and Hand a tone arm I2 adapted to hold a pickup unit 13. A stylus I4 is heldin the pickup unit, the stylus having a pair of record engaging portions15 and 16 extending respectively from the two sides of the-pickupwhereby portion I5 may engage the upper side of record ll rotating inthe clockwise direction, and the point [6 may engage the lower side ofrecord In rotating in the counterclockwise direction.

The stylus M shown in the drawings is disclosed and claimed inapplication Serial No. 90,689, filed *April 30, 1949, assigned to thesame assigne'e as the .present'applicatiom-and entitled Two-SidedStylus, that application being a division of the present application.

Record changing apparatus as such forms no part of the present inventionand is not disclosed. It will be understood that any well known ap-'-paratus may be used in which records 10 and H are rotated at the propertimes relative to stylus portions {-5 and i6. Tone "arm 12 may be one ofany well known construction andis illustrated :by way of example ascomprising a hollow strucresilient material,

ture into which the pickup cartridge 13 may be received bodily, thepickup cartridge including a pair of contact prong I! for conductingelectrical impulses therefrom to suitable amplifying and reproducingapparatus. A spring l8 may be attached to the inside of the tone arm forholding the pickup therein and a stop 2! may be provided for determiningthe inward position of the pickup.

The tone arm holding pickup l3 may be lowered onto record I i and may bemoved upwardly so that stylus portion [6 may engage the lower side ofrecord I U, or the record I maybe lowered onto the stylus withoutdeparting from the scope of the invention.

Referring to Fig. 3, pickup I3 is a unitary struc- 1 ture comprisingupper and lower casing members 22 and 23 which may be formed as shown byany suitable operation, such as by stamping or casting, and from anysuitable material such as brass, aluminum or plastic, As shown, members22 and 23 together form essentially va forward compartment 24 and arearward compartment 25. The forward compartment 24 is formed by anindented portion in casing members 22 and 23, which indented portionholds a bearing member 26 which may be formed of rubber or other forexample, the bearing member supporting one end of a drive unit 21.

The other end of drive unit 21 is supported in a bearing at the frontend of chamber 24, which bearing comprises a rubber or' other resilientmember 28. Bearing members also 26' and 28 absorb minor vibrations ofdrive unit 21.

Within chamber 25 a translating element 29, such as a Rochelle saltcrystal, is supported by means of damping members 3! at the rear endthereof and damping members 32 at the forward end thereof, deformationsof the crystal of course producing an electrical output. The electricaloutput is conducted through conductors 33 to prongs I! which aresupported by an insulating member 34 held between casing members 22 and23. At the forward end of the translating element there are a pair ofstraps forming a yoke 35 which engages a flat connecting member 36through a pair of resilient members 31,'the connecting member 36 formingan integral part of a drive unit 21. On each side of connecting member36 there are a pair of vibration damping resilient supporting members38. Theresilient members 3|, 32 and 38 may be formed of any well knownmaterial, such for example as rubber or a viscoloid, one form of whichis Du Pont Pyralin, Type X-245(), and preferably are formed of suchmaterials having some resilience as well as the ability to absorbenergy. Consequently, these members form dampin elements to preventundesirable resonances of the various structural elements. Resilientmembers 3'! between straps 35 and connecting member 36 form a resilientconnection between drive member 21 and crystal 29 to take account of thefact that crystal 29 may be very stiff and hence should be subjected torelatively small deformations. By virtue of coupling members 31, thestylus I4 may follow the undulations in phonograph record grooveswithout placing undue stress on the crystal. I

Substantially centrally of drive member 21 there is a hole 40 extendingtherethrough having its axis lying at an angle to the axis of the drivemember, whereby stylus I4, held within hole 40, is held at the angledesired relative to recorcls I0 and II. Top member 22 and bottom member23 respectively include openings 39 and 4| substantially in axialalignment with hole 40 in order that the stylus members i 5 and is mayproject therethrough as shown.

Referring to Figs. 3 and 4, stylus I4 includes a central enlargedportion 42 from which the record engaging portions l5 and I6 extend atthe respective ends, the portion 42 being of sufficient length so as toextend completely through the hole in driving member 2'! and approachclosely to the outside of the front portions of casing members 22 and23. Portion 42 also is of sufficient diameter so as to form a very rigidsection for holding the stylus within the hole 40 when engaged by ascrew 43 which is axially threaded in the drive member. Stylus portions15 and it are smaller in diameter than central portion 42 and arereverse curved in form whereby a desirable amount of resiliency isimparted thereto. Accordingly, portions :5 and I6 are spaced on eachside of the axis of portion 42, and terminate respectively in recordengaging points 44 and 45. The record engaging point 44 is spacedforwardly of portion 42 for engaging record H rotating in the clockwisedirection at the optimum point, and the record engaging point 45 isspaced rearwardly of portion 42 for engaging record lli rotatingcounterclockwise, also at the optimum point.

Central portion 42 is provided with a generally conical hole 46 forreceiving the correspondingly shaped end of screw 43 for holding thestylus within hole 40. Since the portion 42 is at an angle to the axisOf screw 43, and the axis of hole 46 coincides with that of screw 43,the hole 46 has an unsymmetrical disposition in portion 42. Inconsequence thereof, the stylus is not reversible and must be placedwithin the hole 38 with the same position at all times.

Otherwise the screw 43 will not be received with in hole 46 at theproper angle with the consequence that the points 44 and 45 would notproject equally on each side of the pickup. In order that the stylus maybe properly placed in hole 38 so that the portion l5 projects from thebottom of the pickup and the portion 16 projects from the top thereof,portion i5 may be colored differently than 16. For example portion i5may be painted black and portion i6 may be painted white. When thestylus has been placed through hole 38 with portion i5 projecting fromthe bottom of the pickup, the approximate centering of the stylus may beindicated by a coating of paint 4'! surrounding central portion 42. Thecoating of paint may have an extent approximating that of portion 42 sothat whenever this band is completely obscured within the pickup thestylus is approximately centered. Whereupon tightening of screw 23forces the point into hole 46 and centers the stylus exactly, since thestylus will move in order that hole 46 conforms to the point of screw43.

The axes Of points 44 and 45, that is lines bisecting these points,preferably lie parallel to the axis of portion 42, and in order that thestylus may be removed from the pickup and placed therein, the dimensionsof holes 40; 39 and 4| are made sufiiciently large to accommodate thereverse curves of portions l5 and [6;

Referring to Fig. 5 a pickup and records are shown corresponding tothose of the previous fig'-' ures. Instead of having a single styluswith two record engaging points, the drive member 21 is provided withholes for receiving screws 48 and 49 which hold a pair of styluses 5]and 52 to the opposite sides of the drive'inember. The two parts of thecasing .22 and .23 are provided with sufficiently large .holes in orderthat a screwdriver may be inserted externally to remove or fasten thestyluses .to the drive member and at the same time to permit thestyluses to project at the desired angle. The styluses may be formedwith ,anattachingarm having suitable points 53 and 5.4 respectively atthe ends thereof, these points being made, for example, of hardenedsteel .or jewel members such as sapphire. The axis of the recordengaging points are parallel to each other and the points occupysubstantially the same positions as the points of stylus 14.

While particular embodiments of the invention have been shown, it willbe understood, of course, that the invention is not limiteed theretosince many modifications may be made, and itis, therefore, contemplatedby the appended claims to cover any such modifications as fall withinthe true spirit and scope of the invention.

Having thus described the invention, what is claimed and desired to besecured by Letters Patent is:

1. A two-sided phonograph pickup comprising a casing, a translatingelement therein, drive means operable to actuate said element, saiddrive means having a transverse hole extending therethrough, a doubleended stylus comprising a shank portion and a record engaging portionhaving a record engaging point at each end thereof, said shank and saidrecord engaging portions being a unitary combination receivable as suchwith said shank portion in said hole, said shank member including arecess, said recess including upper and lower wall surfaces and sidewall surfaces, and a clamping member coacting with said drive means tourge the end of said clamping member into said recess, the end of saidclamping member engaging with said upper and lower wall surfaces toposition said stylus transversely of said pickup, and engaging the saidside wall surfaces to position said stylus rotationally in said pickup.

2. A two-sided phonograph pickup comprising a casing, a translatingelement therein, drive means operable to actuate said element, saiddrive means having a transverse hole extending therethrough, a doubleended stylus comprising a shank portion and a complaint record engagingportion having a record engaging point at each end thereof, said shankand said record engaging portions being a unitary combination receivableas such with said shank portion in said hole, said shank memberincluding a recess, said recess including upper and lower wall surfacesand side wall surfaces, and a clamping member coacting with said drivemeans to urge the end of said clamping member into said recess, the endof said clamping member engaging with said upper and lower wall surfacesto position said stylus transversely of said pickup, and engaging thesaid side wall surfaces to position said stylus rotationally in saidpickup.

3. A two-sided phonograph pickup comprising a casing, a translatingelement therein, drive means operable to actuate said element, saiddrive means having a transverse hole extending therethrough, a doubleended stylus comprising a shank portion and a record engaging portionhaving a record engaging point at each end thereof, said shank and saidrecord engaging portions being a unitary combination receivable as suchwith said shank portion in said hole, said shankImember including asubstantially conical :recess, said 'recess including upper and lowerwall surfaces and side wall surfaces, and a clamping screw threaded intosaid drive means for urging the end of said screw into said conicalrecess, the end of "said clamping member engaging with said upper andlower wall surfaces to position said stylus transversely of said pickup,and engaging the said side Wall surfaces to position said stylusrotationally in said pickup.

4. A two-sided phonograph pickup comprising a casing, a translatingelement therein, drive means operable to actuate said element, saiddrive means having a transverse hole extending therethrough, a doubleended stylus comprising a shank portion, a record engaging portion ateach end thereof and a record engaging tip at the end of each of saidrecord engaging portions and laterally displaced from said shankportion, said shank and said record engaging portions being a unitarycombination receivable as such with said shank portion in said hole,said shank member including a recess, said recess including upper andlower wall surfaces and side wall surfaces, the axis of said recesslying in the plane determined by said shank portion and said recordengaging portions, the end of said clamping member engaging with saidupper and lower wall surfaces to position said stylus transversely ofsaid pickup, and engaging the said side wall surfaces to position saidstylus rotationally in said pickup.

5. A two-sided phonograph pickup comprising a casing, a translatingelement therein, drive means operable to actuate said element, saiddrive means having a transverse hole extending therethrough, a doubleended stylus comprising a shank portion and a record engaging portionhaving a record engaging point at each end thereof, said shank and saidrecord engaging portions being a unitary combination receivable as suchwith said shank portion in said hole, said shank member including arecess, said recess including upper and lower wall surfaces and sidewall surfaces, and a clamping member coacting with said drive means tourge the end of said clamping member into said recess, the end of saidclamping member engaging with said upper and lower wall surfaces toposition said stylus transversely of said pickup, and engaging the saidside Wall surfaces to position said stylus rotationally in said pickup,one of said record engaging portions including indicia for indicatingthe orientation of said stylus in said pickup.

6. A two-sided phonograph pickup comprising a casing, a translatingelement therein, drive means operable to actuate said element, saiddrive means having a transverse hole extending therethrough, a doubleended stylus comprising a shank portion and a record engaging portionhaving a record engaging point at each end thereof, said shank and saidrecord engaging portions being a unitary combination receivable as suchwith said shank portion in said hole, said shank member including arecess, said recess including upper and lower wall surfaces and sidewall surfaces, and a clamping member coacting with said drive means tourge the end of said clamping member into said recess, the end of saidclamping member engaging with said upper and lower wall surfaces toposition said stylus transversely of said pickup, and engaging the saidside wall surfaces to position said stylus rotationally in said pickup,one of said record engaging portions including indicia for indicat- 7ing the orientation of said stylus in saidpickup, said shank means beingadapted toindicate approximate location of said stylus and said pickup.

BENJAMIN B. BAUER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,103,829 Possons July 14, 19141,270,526 Keen et a1 June 25, 1918 Number 1,362,173 1,775,510 1,848,9731,992,893 2,265,840

Name Date Moser Dec. 14, 1920 Caputo Sept. 9, 1930 Penteado Mar. 8, 1932Thomas Feb. 26, 1935 Hutter Dec. 9, 1941 Guedon June 1, 1943 Capps Sept.7, 1943 Graveley Dec. 7, 1943 Bauer Dec. 14, 1948 Andrews Aug. 23, 1949

